Java tutorial
/* * * This file is part of the iText (R) project. Copyright (c) 1998-2019 iText Group NV * Authors: Balder Van Camp, Emiel Ackermann, et al. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License version 3 * as published by the Free Software Foundation with the addition of the * following permission added to Section 15 as permitted in Section 7(a): * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY * ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT * OF THIRD PARTY RIGHTS. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS * FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more * details. You should have received a copy of the GNU Affero General Public * License along with this program; if not, see http://www.gnu.org/licenses or * write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, * Boston, MA, 02110-1301 USA, or download the license from the following URL: * http://itextpdf.com/terms-of-use/ * * The interactive user interfaces in modified source and object code versions * of this program must display Appropriate Legal Notices, as required under * Section 5 of the GNU Affero General Public License. * * In accordance with Section 7(b) of the GNU Affero General Public License, a * covered work must retain the producer line in every PDF that is created or * manipulated using iText. * * You can be released from the requirements of the license by purchasing a * commercial license. Buying such a license is mandatory as soon as you develop * commercial activities involving the iText software without disclosing the * source code of your own applications. These activities include: offering paid * services to customers as an ASP, serving PDFs on the fly in a web * application, shipping iText with a closed source product. * * For more information, please contact iText Software Corp. at this address: * sales@itextpdf.com */ package com.itextpdf.tool.xml; import com.itextpdf.tool.xml.exceptions.LocaleMessages; import com.itextpdf.tool.xml.exceptions.RuntimeWorkerException; import com.itextpdf.tool.xml.parser.XMLParserListener; import com.itextpdf.tool.xml.pipeline.ctx.WorkerContextImpl; import java.util.Map; /** * The implementation of the {@link XMLParserListener}.<br /> * <strong>Important Note</strong>: This class the XMLWorker stores the * {@link WorkerContext} (Which is a {@link WorkerContextImpl}) in a ThreadLocal * variable, WorkerContext is confined to threads here. * * @author redlab_b * */ public class XMLWorker implements XMLParserListener { protected final Pipeline<?> rootpPipe; private static ThreadLocal<WorkerContextImpl> context = new ThreadLocal<WorkerContextImpl>() { @Override protected WorkerContextImpl initialValue() { return new WorkerContextImpl(); }; }; protected final boolean parseHtml; /** * Constructs a new XMLWorker * * @param pipeline the pipeline * @param parseHtml true if this XMLWorker is parsing HTML, this actually * just means: convert all tags to lowercase. */ public XMLWorker(final Pipeline<?> pipeline, final boolean parseHtml) { this.parseHtml = parseHtml; rootpPipe = pipeline; } public void init() { Pipeline<?> p = rootpPipe; try { while ((p = p.init(getLocalWC())) != null) ; } catch (PipelineException e) { throw new RuntimeWorkerException(e); } } public void startElement(final String tag, final Map<String, String> attr, final String ns) { Tag t = createTag(tag, attr, ns); WorkerContext ctx = getLocalWC(); if (null != ctx.getCurrentTag()) { ctx.getCurrentTag().addChild(t); } ctx.setCurrentTag(t); Pipeline<?> wp = rootpPipe; ProcessObject po = new ProcessObject(); try { while (null != (wp = wp.open(ctx, t, po))) ; } catch (PipelineException e) { throw new RuntimeWorkerException(e); } } /** * Creates a new Tag object from the given parameters. * @param tag the tag name * @param attr the attributes * @param ns the namespace if any * @return a Tag */ protected Tag createTag(String tag, final Map<String, String> attr, final String ns) { if (parseHtml) { tag = tag.toLowerCase(); } Tag t = new Tag(tag, attr, ns); return t; } public void endElement(final String tag, final String ns) { String thetag = null; if (parseHtml) { thetag = tag.toLowerCase(); } else { thetag = tag; } WorkerContext ctx = getLocalWC(); if (null != ctx.getCurrentTag() && !thetag.equals(ctx.getCurrentTag().getName())) { throw new RuntimeWorkerException( String.format(LocaleMessages.getInstance().getMessage(LocaleMessages.INVALID_NESTED_TAG), thetag, ctx.getCurrentTag().getName())); } Pipeline<?> wp = rootpPipe; ProcessObject po = new ProcessObject(); try { while (null != (wp = wp.close(ctx, ctx.getCurrentTag(), po))) ; } catch (PipelineException e) { throw new RuntimeWorkerException(e); } finally { if (null != ctx.getCurrentTag()) ctx.setCurrentTag(ctx.getCurrentTag().getParent()); } } /** * This method passes encountered text to the pipeline via the * {@link Pipeline#content(WorkerContext, Tag, String, ProcessObject)} * method. */ public void text(String text) { if (text.startsWith("<![CDATA[") && text.endsWith("]]>")) { if (ignoreCdata()) return; else text = text.substring(9, text.length() - 3); } WorkerContext ctx = getLocalWC(); if (null != ctx.getCurrentTag()) { if (text.length() > 0) { Pipeline<?> wp = rootpPipe; ProcessObject po = new ProcessObject(); try { while (null != (wp = wp.content(ctx, ctx.getCurrentTag(), text, po))) ; } catch (PipelineException e) { throw new RuntimeWorkerException(e); } } } } /* * (non-Javadoc) * * @see * com.itextpdf.tool.xml.parser.ParserListener#unknownText(java.lang.String) */ public void unknownText(final String text) { // TODO unknown text encountered } /* * (non-Javadoc) * * @see * com.itextpdf.tool.xml.parser.ParserListener#comment(java.lang.String) */ public void comment(final String comment) { // TODO xml comment encountered } /* (non-Javadoc) * @see com.itextpdf.tool.xml.parser.XMLParserListener#close() */ public void close() { closeLocalWC(); } /** * Returns the current tag. * @return the current tag */ protected Tag getCurrentTag() { return getLocalWC().getCurrentTag(); } /** * Returns the local WorkerContext, beware: could be a newly initialized * one, if {@link XMLWorker#close()} or {@link XMLWorker#closeLocalWC()} has been called before. * * @return the local WorkerContext */ protected static WorkerContext getLocalWC() { return context.get(); } protected static void closeLocalWC() { context.remove(); } protected boolean ignoreCdata() { return true; } }